Not sure if what Winnebago builds qualifies as a "conversion", but I saw one of these last night.
http://www.gowinnebago.com/products/2014/trend/
The new Trend is kinda fugly, just a big square box looking from the back, but there was a RAM Promaster cab
peeking out from under the built on RV body.
I could not believe the length of the rear overhang, and it looked like it had some sort of receiver hitch on the back.
Chassis:
Here's what I just found on the Winnebago Trend website about the chassis and the receiver hitch:
Ram ProMaster Chassis 280-hp. 3.6L V6 gas engine, 6-speed automatic 62TE transmission, 220-amp. alternator
Trailer Hitch
2,000-lb. drawbar/200-lb. maximum vertical tongue weight and wiring w/4-pin connector.
The trailer hitch capacity is VERY limited to be sure!
Not sure why, but the driver of the Trend did an almost 360 deg. drive around look at my 2014 Sprinter Cargo Van.
Do you suppose he wished he'd bought the Winnebago built on the Sprinter Cab/Chassis instead of the
RAM Promaster?
Roger